Titanium oxide and process of producing same



Patented Jan. 7, 1930 UNITED STATES.

PATENT OFF-ICE FOORD VON BICEOWSKY, 0F GLENDALE, CALIFORNIA, ASSIGNOR TOTITANIA CORPORA- TION, OF LOS ANGELES, CALIFORNIA, A

CORPORATION CALIFORNIA TITANIUM OXIDE AND PROCESS OF PRODUCING SAME NoDrawing.

Thisinvention relates to synthetic titanium titanium oxide and titaniumoxide contain- 5 ing materials through the employment of said reactivetitanium nitrogen compounds, and has for its primary object theutilization of titanium nitrogen compounds which will be readilyattacked by nitricacid and oxidized thereby in contradistinction toknown characteristics of titanium nitrogen compounds which are notsubject to attack by nitric acid.

It is known, (Comptes rendus vol. 82, p, 974), that the titanium nitrideobtained through heating titanium dioxide in a current of dry ammoniagas is soluble in boiling con centrated sulphuric acid; and in Zeit.,anorgund allgem., Chem., vol. 143, part4, p. 299, we find that thenitride of titanium prepared by heating titanium oxide with carbon inthe presence of nitrogen gas is unattacked byboiling sulphuric acid.

Prepared according to either of the above noted ways, the nitridecorresponds to the formula TigNg'.

It is further observed, Zeit., anorg. und -allgem., Chem, vol. 143, part4, p. 299, that titanium'nitride of the above composition is unattackedby nitric acid and that (Textbook of Inorganic Chemistry, vol. 5,edition of 1917, edited by Friend, page 254) cyanonitride Ti C N is alsounafiected by this acid I'have discovered that the nitride of titaniumas preparedby the process recited in United States Letters Patent datedMarch 7, 1922, through the catalytic action of, iron and sodiumcarbonate upon titanium oxide and carbon when heated in the presence ofnitrogen, is not only easily acted upon by hot sulphuric acid, but, andin contradistinction to all known titanium nitrogen 1,

compounds, is readily attacked by even weak nitric acid. In viewthereof, I will hereinafter refer to it as reactive nitride or reactivetitanium nitride or reactive titanium nitrogen compound, so as todifferentiate it from the heretofore known and de- Application filedJune 15, 1927. Serial No. 199,135.

scribed titanium nitride (Ti- N or titanium cyanonitride (Ti 'C N madein the art, it is said that-one gram of reactive nitride was heated inrawater bath with 15 cc. of aweak nitric acid obtained by diluting onevolume of nitric acid (sp; g. 1.42) with two volumes of water, to atemperature of about C. In a few days the brass colored nitride waschanged complete- 1y into the white dioxide with a resultingreaction asfollows:

I I am able. to obtain titanium oxide in an extremely fine state ofdivision which may beused as a basis for a pigment or, becausecompounds. The reaction can beyhastened As indicative of the advancewhichcI have by increasing the temperature or heat at greater or lessthan atmospheric pressure. 7

Advantage can be taken of this action of HNO upon'the reactive titaniumnitride to formed into bring the oxide of titanium as solution withsulphuric acid. As an example: nitride in 10 cc. of concentratedsulphuric To a suspension of 1 gram of reactive.

acid held at 50C. there is very gradually added 2 grams of sodium"nitrate. ,At the end of 100 hours-the sulphuric acid is allowed to cooland is then poured into 100. cc. of cold water. Practically all of thetitanium goes into solution as titanium sulphate. By boiling thissolution the titanium therein contained can be precipitated asTiO J IIn.the above mentioned illustration, ni-

trio acid is formed in the well known way,

through the action of sulphuric acid upon the nitrate of soda.

The nitric-acid so f formed, in turn, decomposes the reactive titaniumnitride into titanium oxide which,

eing in a very activestate, verted by the H 80; present into titaniumsulphate. In this instance, about one-third into ammonia while theremainder is evolved as nitrogen gas which, as it esca s, serves toagitate the sulphuric acid and t us is readily con- I of the nitrogen ofthe nitride is eonverted I keep the material in suspension. If desired,mechanical agitation can also be supplemented. s 1 One commercialapplication of the invention is as follows: Mix the reactive nitridewith-blanc fixe, in the desired proportion; in the precipitation tank,filter or settle the precipitate, and moisten the damp, cake thusobtained with nitric acid and heat with or 1 without stirring until thenitride is decomposed. Upon calcining the blanc fixe, containing thefinely divided TiO all excess HNO is drivenofi' and may be recovered. Iam thus ableto obtain in this manner,

and very cheapl an excellent titanium oxide-barium sulp ate mixture thatonly. re-

quires to be ground to render it suitable for use as a pigment or forother purposes.

Should the reactive titanium nitrogen compound contain a slight amountof iron, I add, towards the close of the reaction of the nitric acidupon it, a small amount of hydrochloric acid or chlorine or sulphuricacid, in orderto bring any iron present into a soluble 'form. If thereactive nitride contains traces of chromium or vanadium comounds, thenitric acid treatment facilitates ringing these elements into solution.4 In practicing the invention, it will be understood that I am not to belimited to the exact proportions of parts, times, tempera-, tures orpressures, and that such variations cambe-resorted to as fall, withinthe scope of the hereto appended claims.

What I claim as my invention is:

l. The process of producing titanium oxygen containing material fromreactive titanium nitrogen compounds, which consists in acting uponthese compounds with nitric 40 acid.

2. The process of producing pure dioxide of titanium from reactivetitanium nitrogen compounds which comprises heating said compounds inthe presence of sulphuric acid 4 v and a metallic nitrate.

3. The process of producing pure dioxide .of titanium from reactivetitanium nitrogen compounds which comprises heating said compounds inthe presence of sulphuric acid 59 and sodium nitrate.

4;. The process of producing pure dioxide. of titanium from reactivetitanium nitride Ti N which comprises heating same in the presence ofsulphuric .acid and sodium nitrate. r

5. The process of producing pure dioxide of titanium from pure-reactivetitanium nitrogen compounds which comprises acting upon said compoundswith nitric'acid in the C0 presence of sulphuric acid.

FOORD VON BICHOWSKY.

